从VF向SQLServer导入数据

VF表mytable(aa D)字段aa,日期类型
在sqlserver中用import data 导入,
create Table complete,copy data from mytable fail
错误提示:
  Error at Destination for Row number 1.Errors encountered so far in this task: 1.insert error,column 1('aa',DBTYPE_DBTIMESTAMP),status 6: Data overflow.Invalid character value for cast specification.
求nothing指点!